1. Field of the Invention
The present invention relates to a method for setting the clamping force exerted by a parking brake.
2. Description of Related Art
Automatic parking brakes (APBs), with which a braking force is continuously exerted in a vehicle while it is stationary, are known. The parking brake is locked, and released again, by way of an actuation element in the vehicle; the actuation generated by the driver results, in a closed- or open-loop control device, in an actuating signal with which control is applied to a braking apparatus, for example an electric motor or a hydraulic pump, to generate braking force at the wheels of the vehicle. Electric motor-based braking apparatuses encompass an electric motor that is disposed on the brake caliper and that acts via a linkage, for example a step-down linkage having a spindle drive, directly on the brake cylinder of the hydraulic brake system. The electric motors are dimensioned so that with them alone, it is possible to set a clamping force with which a vehicle can be held in energyless fashion on 20% slopes. In the case of electric motors of smaller dimensions, or a smaller linkage step-down ratio, the hydraulic braking apparatus is additionally actuated in order to increase the clamping force to the necessary value.